1997 MITSUBISHI TRITON heater

MPI ± Troubleshooting13A-65
Terminal No.Normal condition Check condition (Engine condition) Check item
35Oxygen sensor heaterEngine: Idling after warming up0±3V
Engine r/min: 5,000r/min.System voltage
36Engine warning lampIgnition switch: OFF
ON0 ± 3V
9 ± 13V
(After several seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering
wheel is stationarySystem voltage
When steering
wheel is turned0±3V
38Control relay
(Power supply)
Ignition switch: OFFSystem voltage
(Power su ly)
Ignition switch: ON0±3V
45A/C switchEngine: Idle speedTurn the A/C
switch OFF0±3V
Turn the A/C
switch ON (A/C
compressor is
operating)System voltage
51Ignition switch ± STEngine: Cranking8V or more
52Intake air temperature
sensorIgnition switch:
ONWhen intake air
temperature is
0
C3.2 ± 3.8V
When intake air
temperature is
20
C2.3 ± 2.9V
When intake air
temperature is
40
C1.5 ± 2.1V
When intake air
temperature is
80
C0.4 ± 1.0V
56Oxygen sensorEngine: Running at 2,500 r/min after
warmed up (Check using a digital type
voltmeter)0
0.8V
(Changes repeatedly)
60Backup power supplyIgnition switch: OFFSystem voltage
61Sensor impressed
voltageIgnition switch: ON4.5 ± 5.5V
62Ignition switch ± IGIgnition switch: ONSystem voltage

MPI ± Troubleshooting13A-68
Terminal No. Normal condition (Check condition)Inspection item
4±12Stepper motor coil (A1)28 ± 33 W (At 20
C)
17 ± 12Stepper motor coil (A2)
5±12Stepper motor coil (B1)
18 ± 12Stepper motor coil (B2)
6±12EGR control solenoid valve36 ± 44 W (At 20
C)
9±12Purge control solenoid valve36 ± 44 W (At 20
C)
13 ± Body earthEngine-ECU earthContinuity (0W)
26 ±Body earthEngine-ECU earth
35 ± 12Oxygen sensor heaterApprox. 12 W (At 20
C)
52 ± 72Intake air temperature sensor5.3 ± 6.7 kW (When intake air temperature is 0
C)
2.3 ± 3.0 kW (When intake air temperature is 20
C)
1.0 ± 1.5 kW (When intake air temperature is 40
C)
0.30 ± 0.42 kW (When intake air temperature is 80
C)
63 ± 72Engine coolant temperature sensor5.1 ± 6.5 kW (When coolant temperature is 0
C)
2.1 ± 2.7 kW (When coolant temperature is 20
C)
0.9 ± 1.3 kW (When coolant temperature is 40
C)
0.26 ± 0.36 kW (When coolant temperature is 80
C)
67 ± 72Idle position switchContinuity (when throttle valve is at idle position)
No continuity (when throttle valve is slightly open)
71 ±Body earthInhibitor switch Continuity (when select lever is at P or N)
No continuity (when select lever is at D, 2, L or R)

ENGINE ELECTRICAL ± Charging System16-6
This test determines whether the alternator output
current is normal.
(1) Before the test, always be sure to check the
following.

Alternator installation

Battery (Refer to GROUP 54 ± Battery.)
NOTE
The battery should be slightly discharged.
The load needed by a fully-charged battery
is insufficient for an accurate test.

Alternator drive belt tension (Refer to
GROUP 11 ± On-vehicle Service.)

Fusible link

Abnormal noise from the alternator while
the engine is running.
(2) Turn the ignition switch off.
(3) Disconnect the negative battery cable.
(4) Disconnect the alternator output wire from the
alternator ªBº terminal. Connect a DC test
ammeter with a range of 0 ± 100 A in series
between the ªBº terminal and the disconnected
output wire. (Connect the (+) lead of the
ammeter to the ªBº terminal. Connect the (±)
lead of the ammeter to the disconnected output
wire.)
Caution
Never use clips but tighten bolts and nuts
to connect the line. Otherwise loose
connections (e.g. using clips) will lead to
a serious accident because of high current.
NOTE
An inductive-type ammeter which enables
measurements to be taken without
disconnecting the alternator output wire should
be recommended.
(5) Connect a voltmeter with a range of 0 ± 20 V
between the alternator ªBº terminal and the
earth. (Connect the (+) lead of the voltmeter
to the ªBº terminal, and then connect the (±)
lead of the voltmeter to the earth.)
(6) Connect the negative battery cable.
(7) Connect a tachometer. (Refer to GROUP 11
± On-vehicle Service.)
(8) Leave the hood open.
(9) Check that the reading on the voltmeter is equal
to the battery voltage.
NOTE
If the voltage is 0 V, the cause is probably
an open circuit in the wire or fusible link between
the alternator ªBº terminal and the battery (+)
terminal.(10)Turn the light switch on to turn on headlamps
and then start the engine.
(11) Immediately after setting the headlamps to high
beam and turning the heater blower switch to
the high revolution position, increase the engine
speed to 2,500 r/min and read the maximum
current output value displayed on the ammeter.
Limit: 70% of normal current output
NOTE

For the nominal current output, refer to the
Alternator Specifications.

Because the current from the battery will
soon drop after the engine is started, the
above step should be carried out as quickly
as possible in order to obtain the maximum
current output value.

The current output value will depend on
the electrical load and the temperature of
the alternator body.

If the electrical load is small while testing,
the specified level of current may not be
output even though the alternator is normal.
In such cases, increase the electrical load
by leaving the headlamps turned on for
some time to discharge the battery or by
using the lighting system in another vehicle,
and then test again.

The specified level of current also may not
be output if the temperature of the alternator
body or the ambient temperature is too
high. In such cases, cool the alternator and
then test again.
(12)The reading on the ammeter should be above
the limit value. If the reading is below the limit
value and the alternator output wire is normal,
remove the alternator from the engine and
check the alternator.
(13)Run the engine at idle after the test.
(14)Turn the ignition switch off.
(15)Remove the tachometer.
(16)Disconnect the negative battery cable.
(17)Disconnect the ammeter and voltmeter.
(18)Connect the alternator output wire to the
alternator ªBº terminal.
(19)Connect the negative battery cable.

54-3
REAR WINDOW DEFOGGER 83. . . . . . .
SPECIAL TOOL 83. . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE 83. . . . . . . . . . . . . . . . .
Printed-heater Line Check 83. . . . . . . . . . . . . . . .
REAR WINDOW DEFOGGER SWITCH 84. . .
RADIATOR FAN MOTOR
Refer to GROUP 14 . . . . . . . . . . . . . . . . . . .
INTERCOOLER (INTERCOOLER FAN
MOTOR) Refer to GROUP 15. . . . . . . . . .
REAR DIFFERENTIAL LOCK
Refer to GROUP 27 . . . . . . . . . . . . . . . . . . .
SERVICE BRAKES (ABS)
Refer to GROUP 35B, 35C . . . . . . . . . . . .
DOOR GLASS AND REGULATOR
(POWER WINDOWS)
Refer to GROUP 42 . . . . . . . . . . . . . . . . . . . DOOR HANDLE AND LATCH (DOOR
LOCKING) Refer to GROUP 42. . . . . . . .
WINDSHIELD WIPER AND WASHER
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
HEADLAMP WASHER
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
DOOR MIRROR (ELECTRONIC
CONTROLLED DOOR MIRROR)
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
FRONT SEAT (HEATED SEAT)
Refer to GROUP 52A . . . . . . . . . . . . . . . . .
SRS AIR BAG
Refer to GROUP 52B . . . . . . . . . . . . . . . . .
HEATER Refer to GROUP 55. . . . . . . . . .
AIR CONDITIONER
Refer to GROUP 55 . . . . . . . . . . . . . . . . . . .

55-2
Vacuum Actuator Check Vehicles> 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Idle-up Solenoid Valve Check Vehicles> 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lever Position Switch Check Vehicles (A/T)> 20. . . . . . . . . . . . . . . . . . . . . . . . . .
HEATER CONTROL ASSEMBLY AND A/C
SWITCH 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HEATER UNIT AND HEATER CORE* 24. . . .
BLOWER ASSEMBLY AND RESISTOR
26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EVAPORATOR
28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . COMPRESSOR AND TENSION
PULLEY* 30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CONDENSER AND CONDENSER FAN
MOTOR 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REFRIGERANT LINE* 35. . . . . . . . . . . . . . . . . . .
ENGINE COOLANT TEMPERATURE
SWITCH 37. . . .
IDLE-UP SYSTEM Vehicles> 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LEVER POSITION SWITCH
40. . . . . . . .
VENTILATORS* 41. . . . . . . . . . . . . . . . . . . . . . . . .

± General Information HEATER, AIR CONDITIONER
AND VENTILATION55-3
GENERAL INFORMATION55200010121
The heater system uses a two-way-flow full-air-mix
system that features high performance and low
operating noise, and includes an independent face
air blowing function and a cool air bypass function.The A/C system is basically the same as the
conventional system, but a new refrigerant system
has been adopted as a response to restrictions
on the use of chlorofluorocarbons.
ItemsSpecifications
Heater unitTypeTwo-way-flow full-air-mix system
Heater control assemblyDial type
CompressorModelInclined-plate type
Dual pressure switch
kPa
High-pressure switchON
OFF: 2,648, OF
F ON: 2,059
kPa
Low-pressure switchON
OFF: 177, OFF
ON: 186
Refrigerant and quantity gR-134a (HFC-134a), Approx. 550 ± 600
SAFETY PRECAUTIONS
Because R-134a refrigerant is a hydrofluorocarbon
(HFC) which contains hydrogen atoms in place of
chlorine atoms, it will not cause damage to the
ozone layer.
Refrigerant R-134a is transparent and colourless
in both the liquid and vapour state. Since it has
a boiling point of ± 29.8
C, at atmospheric pressure,
it will be a vapour at all normal temperatures and
pressures. The vapour is heavier than air,
non-flammable, and nonexplosive. The following
precautions must be observed when handling
R-134a.Caution
Wear safety goggles when servicing the
refrigeration system.
R-134a evaporates so rapidly at normal
atmospheric pressures and temperatures that it
tends to freeze anything it contacts. For this reason,
extreme care must be taken to prevent any liquid
refrigerant from contacting the skin and especially
the eyes. Always wear safety goggles when
servicing the refrigeration part of the A/C system.
Keep a bottle of sterile mineral oil handy when
working on the refrigeration system. Should any
liquid refrigerant get into the eyes, use a few drops
of mineral oil to wash them out. R-134a is rapidly
absorbed by the oil. Next splash the eyes with
plenty of cold water. Call your doctor immediately
even though irritation has ceased after treatment.

General Information/Service Specifications/
Lubricants/Sealant HEATER, AIR CONDITIONER
AND VENTILATION ±55-4
Caution
Do not heat R-134a above 40
C
In most instances, moderate heat is required to
bring the pressure of the refrigerant in its container
above the pressure of the system when charging
or adding refrigerant.
A bucket or large pan of hot water not over 40
C
is all the heat required for this purpose. Do not
heat the refrigerant container with a blow torch
or any other means that would raise temperature
and pressure above this temperature. Do not weld
or steam clean on or near the system components
or refrigerant lines.
Caution
Keep R-134a containers upright when charging
the system.When metering R-134a into the refrigeration system
keep the supply tank or cans in an upright position.
If the refrigerant container is on its side or upside
down, liquid refrigerant will enter the system and
damage the compressor.
Caution
1. The leak detector for R-134a should be used
to check for refrigerant gas leaks.
2. Do not allow liquid refrigerant to touch bright
metal.
Refrigerant will tarnish bright metal and chrome
surfaces, and in combination with moisture can
severely corrode all metal surfaces.
SERVICE SPECIFICATIONS55200030141
ItemsStandard value
Idle speed r/min4G6750+100
4D5750+100
Idle up speed r/min900+50
Resistor (for blower motor) WLO: 2.21, ML: 0.97, MH: 0.35
Resistor (for blower motor) WLO: 2.81, ML: 1.28, MH: 0.33
Air gap (Magnetic clutch) mm0.3 ± 0.6
Engine coolant tempera-
ture switch (for A/C cut-off)
ON (continuity)108 or less
ture switch (for A/C cut-off)
<4D5> C
OFF (no continuity)115 or more
Engine coolant tempera-
ture switch (for condenser
ON (continuity)102 or more
ture switch (for condenser
fan) <4D5> C
OFF (no continuity)97 or less
LUBRICANTS55200040137
ItemsSpecified lubricantsQuantity
Each connection of refrigerant lineZXL100PGAs required
Compressor refrigerant unit lubricant m
ZXL100PG180
SEALANT55200050048
ItemSpecified sealantRemark
Engine coolant temperature switch threaded
part3M Nut Locking Part No. 4171 or equivalentDrying sealant

± On-vehicle Service HEATER, AIR CONDITIONER
AND VENTILATION55-14
Performance Temperature Chart
Garage ambient temperature
C20253540
Discharge air temperature
C3.6 ± 9.54.0 ± 11.07.0 ± 9.011.0 ± 13.8
Compressor high pressure kPa1,1201,2361,8142,050
Compressor low pressure kPa11 5131152175
REFRIGERANT LEAK REPAIR55200150083
LOST CHARGE
If the system has lost all charge due to a leak:
1. Evacuate the system. (See procedure.)
2. Charge the system with approximately one
pound of refrigerant.
3. Check for leaks.
4. Discharge the system.
5. Repair leaks.
6. Replace receiver drier.
Caution
Replacement filter-drier units must be
sealed while in storage. The drier used in
these units will saturate water quickly upon
exposure to the atmosphere. When
installing a drier, have all tools and supplies
ready for quick reassembly to avoid keeping
the system open any longer than necessary.
7. Evacuate and charge system.
LOW CHARGE
If the system has not lost all of its refrigerant charge;
locate and repair all leaks. If it is necessary to
increase the system pressure to find the leak
(because of an especially low charge) add
refrigerant. If it is possible to repair the leak without
discharging the refrigerant system, use the
procedure for correcting low refrigerant level.HANDLING TUBING AND FITTINGS
Kinks in the refrigerant tubing or sharp bends in
the refrigerant hose lines will greatly reduce the
capacity of the entire system. High pressures are
produced in the system when it is operating.
Extreme care must be exercised to make sure that
all connections are pressure tight. Dirt and moisture
can enter the system when it is opened for repair
or replacement of lines or components. The
following precautions must be observed. The
system must be completely discharged before
opening any fitting of connection in the refrigeration
system. Open fittings with caution even after the
system has been discharged. If any pressure is
noticed as a fitting is loosened, allow trapped
pressure to bleed off very slowly.
Never attempt to rebend formed lines to fit. Use
the correct line for the installation you are servicing.
A good rule for the flexible hose lines is keep the
radius of all bends at least 10 times the diameter
of the hose.
Sharper bends will reduce the flow of refrigerant.
The flexible hose lines should be routed so that
they are at least 80 mm from the exhaust manifold.
It is good practice to inspect all flexible hose lines
at least once a year to make sure they are in good
condition and properly routed.
Unified plumbing connections with O-rings, these
O-rings are not reusable.